1. Technical Field
This invention relates generally to hollow corn based snack food products. More particularly, this invention relates to the preparation of a laminated pellet product which delaminates immediately upon cutting, and which then expands upon finish cooking.
2. Description of the Background Art
Corn based snack food products (i.e., snack products made entirely or predominantly from corn flour or corn masa) are well known. Due to the chemical makeup of corn, these products consist almost entirely of starch and have little or no gluten. Consequently, the doughs used to prepare such products are, relatively speaking, not very elastic. Snack products made from corn masa, such as tortilla chips, often are prepared by sheeting the masa, cutting individual pieces and then cooking the pieces via, for example, baking or frying. Snack food products made predominantly from corn flour, such as the well-known Fritos.RTM. brand corn chips, often are prepared by extruding a hydrated corn flour based dough, cutting the extrudate into individual pieces and then finish cooking the individual pieces.
Hollow snack food products produced from corn-based flour, such as Bugles.RTM. brand snack products, are known. They are relatively expensive to ship because of their low bulk density, and their delicate nature makes them susceptible to crushing or breaking. Bugles brand products are believed to be manufactured generally according to a process in which corn grits are steeped in the presence of sodium bicarbonate and then cooked with sucrose, salt and water. The resulting dough is cooled, sheeted and formed into pieces that are dried to shelf-stable pellets at about 12% moisture content. The pellets are fried to form the finished product. See U.S. Pat. No. 3,348,950.
Pellet or "half product" technology is well known in the snack food industry. Snack foods produced as pellet products are characterized by the centralized production of an intermediate pellet-stage product which can be shipped to various remote locations where the finished product is prepared by "finish cooking" the pellets. For the purposes of this disclosure, the term "finish cooking" means subjecting the product to heat and may include one or more of the processes that can occur when farinaceous products are subjected to heat, including dehydration, gelatinization of starches, denaturation of proteins, and the browning of sugars. As used herein, "finish cooking" is, at least, responsible for imparting to the product the desired final textural attributes and moisture content. Finish cooking can be carried out, for example, by subjecting the pellet to frying, baking (hot air impingement), microwave heating, etc. Pellet products offer advantages, including a high bulk density (making them less expensive to ship) and greater resistance to breakage during shipment. Additionally, the use of a pellet process permits portions of the manufacturing process to be centralized. The pellet stage product must be storage stable because, by design, a period of time may elapse between preparation of the pellet and the finish cooking operation.